it depends on the model as well. The first spyders had an angled feedneck that was not removable, then they had feednecks that used holes to hold it on. they used this design until they had the tabbed feednecks; although the victors have always used the hole feednecks up til very recently I believe. When the VS/RS series came out, the feednecks were ION threaded but since then, they use an unknown threading on their feednecks now.